Benjamin f



(No Model.) 2 SheetsSheet 1.,

B. F. HULL. INTEREST CALCULATOR.

Patented Jan I B my com/LnFulL. J 06 whit-meme o v 2 Sh68tS -S1186t BMRHULL, INTEREST CALCULATOR.

(No Model.)

P10444396. Patented Ia-11.61891.

Bag drain Fl'fulL Svweufoz UNITED STATES BENJAMIN F. HULL, OF CLlNTbN,

ILLINOIS, ASSIGNOR 'r'o EMMA IIULL,

orsAME PLACE.

= m-TERssT-oALou LATOR,

SPECIFICATION forming part of Letters Patent No. 444,396, dated January'6,1 891 Application filed July 24, 1890. Serial No. 359.791. (No model.) I

To all whom it may concern:

Be itknown that I, BENJAMIN F. IIUL'L, a citizen of the United States of America, residing at Clinton, in the county of De lVitt and 'State of Illinois, have invented certain new and usefullmprovements in Interest- Calculators; and I do hereby declare the follos'vingto'be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to letters of reference marked thereon, which form a part of this specification.

This invention relates to improvements in devices for calculating interest. a

The object of the invention is to-provide a simple, cheap, and compact device consisting of a frame which is adapted to receive a series'of printed tablets, said frame having in 'its inner sides grooves adapted to receive a sliding scale, which can-be moved over the tables to indicate, in connection with said tables, the amount of interest for a given time upon a given principal; and it consists in the construction and combination of the parts, as

will be hereinafter fully set forth, and particularly pointed out in theclaims.

In the accompanying drawings, forming part of this specification, Figure 1 is a plan view of a calculator constructed in accordance with myinvention. Fig. 2 isatransverse sectional view showing the device closed. Fig. 3 is a front view. Fig. 4 is a side view of one end of the device, showing the fastening, and Fig. 5 is a detail perspective view of a part of the sliding indicator. 1

The frame consists of a back board A, to which are rigidly attached side pieces l3 l3 and an eud'piece C. The side pieces'B B. and end piece C are rigidlyatt'ached to the board A, and project a slight distance above the same to provide an open-ended compartment, within which can be placed a series of tables. The-inner-sides of the pieces B Bare pro vided with longitudinal grooves (I, located about centrally in said side pieces, so that the space beueaththe groove and above the inn'er .face of thmhoard A can'be occ lpied h a series of interest-tables I), which" are'd1-" v1ded into vertical columns havingfigures which. indicate the amount. of interest on designated principles pla'c'ejdat the top and bottom of said'eolurnns'f Each tablelliasa head-line stating the'raft'eot-interest, well; as a: projecting portion (gr-tab (1, upon which therate of interest is indieatedin large figures, as shown." -z' E refers to a sliding indi c timf which moves; within the grooves an and over the tables-J), and the right-handedge of thisindicato printed in a vertical column "figures in'drca tive of time, the upper part of the colulnn .rev fer-ring to days,the"intermediatepo to months, and the lower end to yea W v figures upon said indicator register-rho Z011- tally with the s tnqinals cvstntfig up'onthe table's. Tliisindicater can be moved freely over the: tables, and the numbers thereon, when oppositethe figure ;in t Q. vertical columns of the tables, willggive the interest on the principal, which is noted the top and bottom of the column. f To the s'tripG is secured a coverF, of card-.1 board or other suitable material, to which may be attached by paper fastenin'gs a pad or tablet G, which is of such width, length, and thickness that when the cover is closed it will lie within the space above the tables D g and between the sides B B, so that the sides j of the cover. will lie over the upper edges of the side pieces, as shown in the transverse;- sectional view. The tablet or pad G is made ,1, up of a number of sheets of paper in the usual manner, and'upon which calculations- I can be made.

The back A may be provided witha-s'iltitg able elastic band, which engages with afixture on the free end of the cover, so as to hold the cover closed when the device is. not in-use; o-

Each of the interest-tables is Inadeup'of separate leaves, and the one it is desired 'to useis' withdrawn and placed on top or immediately beneath the indicator. The indicator, whichflcontains the days, months, and 5 years, by being movable avoids the confusionof having to follow two columns at the same. I time, and thus lessens the liability to err in arriving at a correct result, and the arrangement is so simple that the question ofcalculat- [00 ing interestisredueed to mereaddition.

In pra ctice,-supp9sin g that it should be-d e sired to 11nd lllt interest on tort dollars for! three months and twenrr-three days zit eight v per cent, it is (my necessary in insert heneath the indicator the leaf lnivingtheintcrest at eight per cent. The. indicator is then moved to the column of figures headed 54:0.

days and the interest will he found to he dwenty cents. Moving-down to three months 10 the interest will he found to be eighty cents,

. and t\\ent- \'c(-ntspluseighty cents equals one dollar, the :unonnt required. 13y little practice thesmaller amounts can be carried mentally and the interest determined accuratelyand with dispatch. Y

I am aware that'prior'to my invention caleulatingdeviees havins a sliding and i-aduated scale, as shown in patent to G. M. knight, i dated May 8,1883, or patent; to Curtis, March 5 20 1S, 1884, have heretofore been used, and I do fnot claim what is shown therein; lint I -,What I do claim as new, and desire to secure by Lett-erslateni, is,

1-2 1he eombinatit'm, in a device for calcudatiug interest, of a tran'ie having a base with side'pieees l3 and end piece C- rigidly secured 1 thereto, the side pieces being grooved on their inner sides for the reception of a sliding indicator,'a series of removable tables confined "3o beneath the grooves in the side pieces by the l' Y ii-1,396

indicator, a cover hinged to the end strip C and provided with a tablet, said tablet-being i adapted tolie within the end and side pieces when the cover is closed, and a retaining (leviee, substantially as set forth.

The combination, in a device for colonlating interest, of a frame having the inner sides of the upper and lower edges grooved for the reception of a sliding indicator, removable interest-tables, a cover hinged thereto and adapted to lie over the upper edges of theside pieces, aspace being provided within the frame above the interest-tables and slidthe purpose set forth.-

-i n g indicator, substantially asshown, and ifor 3. In combination with a'fraine and tables,

as shown, said frame having formed in its innor sides grooves. or recesses a a, a sliding indicator havinglaterallyextended ends with rounded corners, and acentral connecting portion having a straight edge, the opposite edge lieing upturned to provide a'stitfening and grasping portion, substantially asset forth.

In testimony whereof I atfix' niy' signature in presence of tvvc' \vituasses.

" BENJA-hiiNF. Iii-IL 

